This invention relates to composites and more particularly to metal/carbon composites having high thermal conductivities.
Up to the present, certain metals and alloys of aluminum and magnesium have been used to fabricate the heat sinks which are employed successfully to carry away the heat generated by solid state electronics. Their high thermal conductivity and low density (aluminum: 2.37 W/cm/K, 2.70 g/cc) provided the necessary combination of physical properties for heat sink cooling of lightweight electronic packages.
The very large scale integration (VLSI) of the most recent generation of electronics has put increased demands on the cooling system. Heat must be conducted rapidly away from ever smaller solid state chips. More efficient heat sinks are needed. It has been proposed, for example, to use continuous graphite fiber/aluminum composites for this purpose. The graphite fiber axial thermal conductivity of 300-500 W/m-K can provide a significant unidirectional performance improvement, provided that the continuous fibers remain undegraded and unbroken. While fiber materials costs are reasonable for applications envisioned, fabrication of continuously reinforced MMCs in complex geometry is difficult.
Accordingly it would be desirable to provide a new material having high heat conductivity and which can be fabricated into complex shapes.